Killing Floor

Killing Floor is a Co-op Survival Horror FPS set in the devastated cities and countryside of England after a series of cloning experiments for the military goes horribly wrong. You and your friends are members of the military dropped into these locations with a simple mission: Survive long enough...

I decided to boot up KF1 as I had not played it for a while. First 2 servers I join I get insulted and banned within 20 seconds. Whats up with that? Is this the type of people that play this game now.
http://steamcommunity.com/sharedfiles/filedetails/?...

I was playing it just fine for about an hour, then I upgraded to Windows 10. After I did this I went right back to starting up Killing Floor, I see the game launcher but it gives me an error message.
The message is as follows:
Build UT2004_Build_[2004-...